Filament bulb



FIG. 1 is a perspective upper front View of a filament bulb;

FIG. 2 is a front View thereof;

FIG. 3 is a rear View thereof;

FIG. 4 is a left side View thereof;

FIG. 5 is a right side View thereof;

FIG. 6 is a top plan View thereof;

FIG. 7 is a bottom plan View thereof; and,

FIG. 8 is a perspective lower front View thereof.

In the drawings, the broken lines depict environmental subject matter only and form no part of the claimed design.

The glass plunger surrounding the filament, the lamp holder beneath the filament as well as the screw base are shown in broken lines because they are not part of the claimed design, but are considered necessary to show the environment in which the design is associated.

Secondly, in the center of the filament bulb several groups of vertically oriented LED wires are shown wherein each group contains of two LED wires. Only one group of two LED wires is shown in solid lines. The purpose of showing only one group of two LED wires in solid lines is that the second and any further group of two LED wires are identical to said group of two LED wires that is shown in solid lines. Therefore, any repetition of said group of two LED wires that is shown in solid lines is shown in broken lines. 

CLAIM The ornamental design for a filament bulb, as shown and described. 